Bounding cochordal cover number of graphs via vertex stretching
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Abstract:
It is shown that when a special vertex stretching is applied to a graph, the cochordal cover number of the graph increases exactly by one, as it happens to its induced matching number and (Castelnuovo-Mumford) regularity. As a consequence, it is shown that the induced matching number and cochordal cover number of a special vertex stretching of a graph G are equal provided G is well-covered bipartite or weakly chordal graph.
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Journal title
volume 42 issue 3
pages 679- 685
publication date 2016-06-01
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